Plant holder



FIG. 1 is a top perspective view of a plant holder showing my new design, the broken line showing of a wall being for illustrative purposes only;

FIG. 2 is a bottom view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a left side view thereof. 

The ornamental design for a plant holder, substantially as shown and described. 